It depends on the type of arterial. A bike lane functions the same as a shoulder with
a guide stripe on a bridge or other arterial without cross traffic or parking. When there
is cross traffic, a bike lane leads to conflicts, and where there is parking, the bike
lane requires additional width. Unfortunately, most Cambridge arterials have parking,
insufficient width, and cross traffic at cross streets and driveways. Alternatives: if
parking is the only problem, eliminate parking if the parking ban can be achieved and
enforced. If cross traffic is the problem, and instersections can not be designed so
right-turning motorists pass to the right of through-traveling bicyclists, do not install
bike lanes.